In the calm and rarefied world of haute couture, it is a shot across the bows from Chanel. The fashion house has raised the possibility of moving its couture collection from Paris to New York next season, which would threaten to end a French tradition that dates back to 1858.

The house feels that the couture week, once the centrepiece of handmade creativity in Paris fashion, has become too polluted by mass-produced labels that have piggy-backed their shows on to the official schedule.

"Couture must remain very exceptional and exclusive," Françoise Montenay, the president of Chanel, told the trade paper Women's Wear Daily. "We are adaptable. If things are getting too sad, we might go [to New York]. We are always challenging ourselves."

The comments have been the talk of the past few days of shows, and the future of couture is the source of growing concern.

To move the couture show itself would be an immense operation. Couture relies on the work of the highly skilled seamstresses known as les petites mains. They work all hours in the days running up to the collections. If the show were to move to New York, the entire Chanel operation would have to follow.

"Nothing has been decided, but it's not going to be an easy thing if we do that," said Veronique Perez, fashion director of the Chanel press office. "It will need organisation, otherwise we will have nightmares."

Couture is the tightly controlled discipline of making outfits to a rigid protocol. Like the Jean Paul Gaultier couture dress worn by Nicole Kidman at this year's Oscars, each piece is painstakingly fitted to the individual wearer over a series of fittings. They will be bought by a handful of women worldwide, usually the wives of businessmen from Wall Street or the Middle East, who buy watered down versions of the pieces seen on the catwalk - but at a price. Because of the work required, the clothes can easily cost a five-figure sum.

Because of closures and the retirement of designers, the number of couture shows in Paris has shrunk in recent years to 11, in July and January. Sensing an opportunity, ready-to-wear houses like Yohji Yamamoto have begun to show their collections during couture to benefit from the more relaxed atmosphere.

Chanel is committed to continuing its couture collections designed by Karl Lagerfeld, which are highly profitable. But it is worried that the couture week itself is losing its lustre, especially since the retirement of Yves Saint-Laurent last year. Emanuel Ungaro, who is in his 70s, and who showed yesterday in Paris, is the only working couturier left who was trained by the masters - in his case, Courrèges and Balenciaga.

Chanel said it has not made a final decision about a move. "It is a question of if, if, if," said Ms Perez. "Karl Lagerfeld has already said it is something he might think about in the future. We invest and we believe in couture, and we do what we have to do if it is to evolve."

Mistake

Didier Grumbach, the president of the couture governing body, the Chambre Syndicale, said it would be a mistake for Chanel to leave Paris. "I think that Chanel has no reason to do it," he said. "Lagerfeld's success is unprecedented. You don't move something that works."

However, the threat is a serious one for Mr Grumbach. Alongside John Galliano's work for Christian Dior, Chanel is the highlight of the couture season. If Chanel were to move, Dior has hinted that it would consider following suit.

Without Dior and Chanel, couture would be bereft of globally important designers. Most of the couture houses already travel with their shows once the Paris shows are over. Ungaro is planning to take its collection of simple daywear and modernist-patterned gowns to Dubai, Kazakstan and Los Angeles in the hope of opening up new markets. Representatives of Chanel and Dior already visit New York to fit and perfect the orders made by Americans during the Paris couture shows.

The logic of any move is clear: by showing in New York, Chanel would be dealing directly with some its most affluent and influential clientele. The transfer would also bring the house valuable publicity, and that could be the most important factor.